Achondroplasia is a common form of dwarfism caused by autosomal dominant mutation in the fibroblast growth factor receptor gene 3.If a person with achondroplasia married and had children with a person of normal height,what is the probability that both their first child and second child would have achondroplasia?
A)1/8
B)1/4
C)1/2
D)1

Question

Quizplus · Accepted Answer

Since achondroplasia is caused by an autosomal dominant mutation, there is a 50% chance that the offspring will inherit the mutation from the affected parent. Therefore, the probability of the first child having achondroplasia is 1/2. For the second child, the probability is still 1/2 as each birth is independent of the previous one. The probability of having two independent events occur together is calculated by multiplying the probabilities. Therefore, the probability that both the first and second child will have achondroplasia is (1/2)*(1/2) = 1/4 or 25%.

Achondroplasia Is a Common Form of Dwarfism Caused by Autosomal